Original paper

Topographic swath profile analysis: a generalization and sensitivity evaluation of a digital terrain analysis tool

Telbisz, Tamás; Kovács, Gábor; Székely, Balázs; Szabó, Judit

Abstract

Swath profile analysis is considered to be an improved, DTM-based version of traditional cross-section analysis. To avoid arbitrariness of simple line profiles, the swath method horizontally expands the cross-section line into a rectangular swath. Commonly, profile Z values are calculated as statistical parameters (minimum, mean, maximum, etc.) of elevation values being at the same distance from the baseline of the swath. Swath profile analysis proved to be useful in the study of large orogens to evaluate the effects of vertical surface movements as well as in the investigation of fluvially or glacially sculpted topography. However, there is still a lack of a summarized methodological description that this paper aims to make up for, additionally presenting a brief review of earlier swath-based studies. Although previous studies used the term swath for rectangular units only, we, generalizing its possible usage, extend this analysis to circular and curvilinear polygons as well so that it can be useful in the topographic characterization of volcanoes or large, curved orogens.In order to demonstrate the usefulness and applicability of swath profiles, the method is tested on an artificial surface, first. Secondly, swath profile analysis is applied to a hilly terrain in the Eastern Alpine Foreland, the Western Pannonian Alpine Foothills. This analysis helped to identify topographic rims, tilted remnant surfaces and fluvial incision within the study area, even where these features are obscured by the dissected topography. Using this area as an example, sensitivity to swath width, swath orientation and swath horizontal resolution was assessed in terms of comparison diagrams and numerical statistics (RMSE, tilt and step para meters). As a result, it is concluded that swath profiles and quantitative landform parameters are found in an acceptably narrow range for relatively large changes in width, azimuth and swath resolution that supports the intuitive application of this method.

Keywords

circular swathcurvilinear swathdtmeastern alpine forelandtectonic geomorphology